Contrast Enhanced Ultrasound

A Jefferson Radiology specialty, contrast-enhanced ultrasound (CEUS) is a highly versatile method of expanding the diagnostic capabilities of ultrasound. By injecting less than a teaspoon full of contrast agent containing millions of tiny gas-filled bubbles—themselves the size of red blood cells—into a patient’s blood stream before an ultrasound exam, physicians can get a clearer look at a patient’s blood flow and the organs it supplies.

How It Works

Normally, gas bubbles in the bloodstream, called an embolism, are something physicians work to avoid, but these contrast bubbles are very different. Coated in an electrically charged shell, the bubbles repel each other, preventing the formation of a larger embolism. After about 10 minutes, the bubbles are retained by the liver where they pop harmlessly and the gas they contain is expelled as breath.

While normal tissue is interconnected and relatively rigid, microbubbles, composed of only gas and a biodegradable shell, are flexible enough to create irregular motion and double-beats, which stand out during ultrasound imaging and make them an effective form of contrast. Ultrasound by itself is very good for diagnostic procedures of structures close to the body’s surface, but sonic waves can scatter and become unfocused when aimed at deeper layers of the body. CEUS boosts the returning signal and allows physicians to see deeper and with more clarity than was previously possible with this modality.

Harmonic imaging—setting the ultrasound machine to receive the unique sound waves that vibrate at multiples of the original frequency—is the commercial standard for microbubble contrast. An alternative is subharmonic imaging, an approach pioneered at Jefferson, in which the machine is “tuned” to pick up lower frequency waves. This enables physicians and researchers to take maximum advantage of the bubbles’ physical properties, because normal tissue is able to generate some harmonics, but is too rigid to return subharmonic signals. 


Jefferson's CEUS researchers maintain an extensive portfolio of extra and intramurally funded projects and are always on the lookout for new partners and ideas.